US5814289A - Process for the peparation of cogranulates comprising aluminosilicates and sodium silicates - Google Patents

Process for the peparation of cogranulates comprising aluminosilicates and sodium silicates Download PDF

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Publication number
US5814289A
US5814289A US08/688,354 US68835496A US5814289A US 5814289 A US5814289 A US 5814289A US 68835496 A US68835496 A US 68835496A US 5814289 A US5814289 A US 5814289A
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sub
aluminosilicates
cogranulates
sodium silicates
compact
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US08/688,354
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Alexander Tapper
Gunther Schimmel
Gerd Wingefeld
Hans-Peter Rieck
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Clariant Produkte Deutschland GmbH
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Hoechst AG
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Priority claimed from DE4210253A external-priority patent/DE4210253A1/en
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Assigned to CLARIANT GMBH reassignment CLARIANT GMBH ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HOECHST AKTIENGESELLSCHAFT
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    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/02—Inorganic compounds ; Elemental compounds
    • C11D3/12—Water-insoluble compounds
    • C11D3/124—Silicon containing, e.g. silica, silex, quartz or glass beads
    • C11D3/1246—Silicates, e.g. diatomaceous earth
    • C11D3/128—Aluminium silicates, e.g. zeolites
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/02—Inorganic compounds ; Elemental compounds
    • C11D3/12—Water-insoluble compounds
    • C11D3/124—Silicon containing, e.g. silica, silex, quartz or glass beads
    • C11D3/1246—Silicates, e.g. diatomaceous earth
    • C11D3/1253—Layer silicates, e.g. talcum, kaolin, clay, bentonite, smectite, montmorillonite, hectorite or attapulgite
    • C11D3/1273—Crystalline layered silicates of type NaMeSixO2x+1YH2O

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  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Wood Science & Technology (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Silicates, Zeolites, And Molecular Sieves (AREA)
  • Detergent Compositions (AREA)

Abstract

Cogranulates of high bulk density which easily disintegrate in water and comprise aluminosilicates and crystalline sodium silicates having a layered structure. The aluminosilicates contained therein are those of the formula
M.sub.2/n O.Al.sub.2 O.sub.3. XSiO.sub.2. yH.sub.2 O
in which M is an alkali metal or alkaline earth metal, n indicates the valency of the cation, x is≧2 and y has a value of between 0 and 8. The sodium silicates have an SiO2 /Na2 O ratio of (1.8 to 4.2):1. These cogranulates are prepared by mixing the pulverulent aluminosilicates and sodium silicates with one another and introducing the mixture into a zone in which it is compacted between two rolls rotating in opposite directions to form a compact. After comminution of the compact, the desired particle sizes are finally separated off from the oversize and undersize material. The cogranulates can be used in detergents and cleaning agents.

Description

This application is a continuation of application Ser. No. 08/289,007 filed on Aug. 11, 1994 now abandoned, which is a continuation-in-part of Ser. No. 08/031,546 filed Mar. 15, 1993, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to cogranulates of high bulk density which easily disintegrate in water and comprise aluminosilicates and crystalline sodium silicates having a layered structure, to a process for their preparation and to their use.
2. Discussion of the Related Art
For ecological reasons, phosphate-based builders in detergents and cleaning agents, in particular alkali metal tripolyphosphates, have recently been increasingly replaced by new builder systems which normally comprise a synthetic, crystalline aluminosilicate (for example zeolite A), an alkali metal source (e.g. sodium carbonate) and at least one cobuilder. The cobuilders used are individually or in combination nitrilotriacetic acid or salts thereof, phosphonates and polycarboxylates.
The synthetic, crystalline aluminosilicate used in these builders must be a very finely divided powder having a median particle diameter d50 ≦10 μm. If during preparation of the aluminosilicates, during their processing or in the course of their application larger agglomerates are formed, the purpose of the cobuilders mentioned is to divide the aluminosilicates into a suspension of fine primary particles. This is necessary especially because agglomerates of aluminosilicates, specifically those of zeolite A, do not by themselves show any tendency to disintegrate in water into the primary particles.
The recent appearance of compact detergents on the market has awakened a desire for an increased bulk density of the individual components of detergents and cleaning agents, for example by spray-agglomeration or by compacting. Agglomerates or compacts of aluminosilicates, specifically of zeolite A, produced in this manner usually require an increased use of cobuilders, due to their disinclination to disintegrate in water.
A disadvantage of the cobuilders mentioned is their negative ecological rating. Thus, the polycarboxylates predominantly used today are not biodegradable. For this reason, attempts have been made to obtain an at least predominantly inorganic builder system.
Thus, U.S. Pat. No. 4,737,306 discloses finely divided, water-insoluble layered silicates of the oxide empirical formula
MgO.a M.sub.2 O.b Al.sub.2 O.sub.3.c SiO.sub.2. n H.sub.2 O
in which M is sodium and/or lithium and in which a, b, c and n are a number in the ranges 0.05 to 0.4; 0 to 0.3; 1.2 to 2.0 and 0.3 to 3.0, respectively. These layered silicates, which are suitable as detergent base material in detergents and cleaning agents, are prepared by hydrothermal reaction of water-soluble sodium silicate with oxides, hydroxides or water-soluble salts of magnesium, aluminum and lithium in aqueous solution or suspension at 150° to 250° C. for 1 to 20 hours under autogenous pressure. A disadvantage of the known magnesium- and aluminum-containing layered silicates is that their water-softening effect is low. Accordingly, they must be used in the formulation in a large amount, which, owing to their insolubility in water, considerably increases the amount of sludge in the water treatment plant. Finally, in a builder system, they cannot act as a supplier of alkali.
DESCRIPTION OF THE INVENTION
Accordingly, the object of the present invention is to describe substances based on inorganic compounds which easily disintegrate in water into the primary particles and, as cobuilders, exert a disintegrating effect on agglomerates and compacts. According to the invention, they are cogranulates comprising aluminosilicates and crystalline sodium silicates having a layered structure, the aluminosilicates used being of the formula
M.sub.2/n O.Al.sub.2 O.sub.3.xSio.sub.2. yH.sub.2 O
in which M is an alkali metal or alkaline earth metal, n indicates the valency of the cation, x is≧2 and y has a value of between 0 and 8, the sodium silicates having an SiO2 /Na2 O ratio of (1.8 to 4.2):1.
An optional further feature of the cogranulates according to the invention can be that
a) they contain at least 3% by weight of sodium silicates;
b) they contain zeolite A as the aluminosilicates;
c) their bulk density is at least 700 g/l;
d) the sodium silicates have an SiO2 /Na2 O ratio of (1.9 to 2.1):1.
A process for the preparation of the cogranulates may comprise mixing the aluminosilicates and sodium silicates in pulverulent form with one another; introducing the mixture into a zone in which it is compacted under pressure to form a compact between two rolls rotating in opposite directions; comminuting the compact; and finally separating off the desired particle sizes from the oversize and undersize material.
Finally, the cogranulates according to the invention can be used in detergents and cleaning agents, for example as builders.
The crystalline sodium silicates having a layered structure and being present in the cogranulates according to the invention are slowly water-soluble, as a result of which a reduction in the amount of sludge in the water treatment plants is achieved.
Owing to the water solubility of the crystalline sodium silicates present in the cogranulates according to the invention, sodium carbonate can, if desired, be entirely excluded from the detergent or cleaning agent formulation, since the crystalline sodium silicates act as a supplier of alkali.
Since the crystalline sodium silicates present in the cogranulates according to the invention have a considerable bursting effect, even small amounts of sodium silicate in the cogranulate are sufficient for suspending agglomerates or compacts of aluminosilicate.
The crystalline sodium silicates present in the cogranulates according to the invention have a marked water-softening effect of about 75 mg of Ca/g (measured at 20° C. and a pH of 10.5 using water having a German hardness of 30°).
EXAMPLE 1 (Comparative Example)
30 kg of zeolite A were compacted at a line compacting force of 30 kN/cm in a compactor (from Bepex GmbH) having a roll diameter of 200 mm and then milled to give granules having a d50 of 480 μm. Disintegration of the granulate in water (German hardness of 17°) was tested as a function of time using a MICROTRAC Series 9200 (from Leeds & Nothrup GmbH). In addition, the calcium-binding capacity (CBC) was determined by means of a calcium-sensitive electrode (from Orion Research Inc.) after 10 minutes at 20° C. and a pH of 10.2:
______________________________________                                    
                                    Bulk                                  
d.sub.50   d.sub.50     CBC         density                               
 μm!, after 1 min                                                      
            μm!, after 4 min                                           
                         mg of CaCO.sub.3 /g!                             
                                     g/l!                                 
______________________________________                                    
421.1      405.2        78.1        680                                   
______________________________________
EXAMPLE 2 (Comparative Example)
29.7 kg of zeolite A and 0.3 kg of Na2 Si2 O5 having a layered structure (δ modification) were premixed in an EIRICH mixer. The premixture was compacted analogously to Example 1 and milled to give granules having a d50 of 510 μm. The granules were tested by the procedure of Example 1:
______________________________________                                    
                                    Bulk                                  
d.sub.50   d.sub.50     CBC         density                               
 μm!, after 1 min                                                      
            μm!, after 4 min                                           
                         mg of CaCO.sub.3 /g!                             
                                     g/l!                                 
______________________________________                                    
173.2      138.1        122.2       695                                   
______________________________________
EXAMPLE 3 (according to the invention)
29.1 kg of zeolite A and 0.9 kg of Na2 Si2 O5 having a layered structure (δ modification) were premixed in an EIRICH mixer. The premixture was compacted analogously to Example 1 and milled to give granules having a d50 of 510 μm. The granules were tested by the procedure of Example 1:
______________________________________                                    
                                    Bulk                                  
d.sub.50   d.sub.50     CBC         density                               
 μm!, after 1 min                                                      
            μm!, after 4 min                                           
                         mg of CaCO.sub.3 /g!                             
                                     g/l!                                 
______________________________________                                    
56.7       51.0         170.2       710                                   
______________________________________
EXAMPLE 4 (according to the invention)
21 kg of zeolite A and 9 kg of Na2 Si2 O5 having a layered structure (β modification) were premixed in an EIRICH mixer. The premixture was compacted analogously to Example 1 and milled to give granules having a d50 of 520 μm. The granules were tested by the procedure of Example 1:
______________________________________                                    
                                    Bulk                                  
d.sub.50   d.sub.50     CBC         density                               
 μm!, after 1 min                                                      
            μm!, after 4 min                                           
                         mg of CaCO.sub.3 /g!                             
                                     g/l!                                 
______________________________________                                    
18.9       13.3         187.9       760                                   
______________________________________
EXAMPLE 5 (according to the invention)
Example 3 was repeated, except that 27 kg of zeolite A and 3 kg of Na2 Si2 O5 having a layered structure (δ modification) were premixed in the Eirich mixer:
______________________________________                                    
                                    Bulk                                  
d.sub.50   d.sub.50     CBC         density                               
 μm!, after 1 min                                                      
            μm!, after 4 min                                           
                         mg of CaCO.sub.3 /g!                             
                                     g/l!                                 
______________________________________                                    
36.8       30.3         181.9       720                                   
______________________________________
EXAMPLE 6 (according to the invention)
27 kg of zeolite A and 3 kg of kanemite (NaHSi2 O5 ×3H2 O) were premixed in an EIRICH mixer. The premixture was compacted analogously to Example 1 and milled to give granules having a d50 of 520 μm. The granules were tested by the procedure of Example 1:
______________________________________                                    
                                    Bulk                                  
d.sub.50   d.sub.50     CBC         density                               
 μm!, after 1 min                                                      
            μm!, after 4 min                                           
                         mg of CaCO.sub.3 /g!                             
                                     g/l!                                 
______________________________________                                    
50.1       44.2         176.3       560                                   
______________________________________
EXAMPLE 7 (according to the invention)
27 kg of zeolite A and 3 kg of makatite (Na2 Si4 O9 ×5H2 O) were premixed in an EIRICH mixer. The premixture was compacted analogously to Example 1 and milled to give granules having a d50 of 534 μm. The granules were tested by the procedure of Example 1:
______________________________________                                    
                                    Bulk                                  
d.sub.50   d.sub.50     CBC         density                               
 μm!, after 1 min                                                      
            μm!, after 4 min                                           
                         mg of CaCO.sub.3 /g!                             
                                     g/l!                                 
______________________________________                                    
43.2       37.9         153.7       725                                   
______________________________________

Claims (1)

We claim:
1. A process for the preparation of cogranulates having a bulk density of at least 700 g which easily disintegrate in water and consist essentially of aluminosilicates and crystalline sodium silicates having a layered structure which process comprises mixing the aluminosilicates and the crystalline sodium silicates having a layered structure in pulverulent form with one another; introducing the mixture into a zone in which it is compacted under pressure between two rolls rotating in opposite directions to form a compact; comminuting the compact; and finally separating off the desired particle sizes from the oversize and undersize material.
US08/688,354 1992-03-28 1996-07-30 Process for the peparation of cogranulates comprising aluminosilicates and sodium silicates Expired - Fee Related US5814289A (en)

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US08/688,354 US5814289A (en) 1992-03-28 1996-07-30 Process for the peparation of cogranulates comprising aluminosilicates and sodium silicates

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE4210253A DE4210253A1 (en) 1992-03-28 1992-03-28 Cogranulates consisting of aluminosilicates and sodium silicates, a process for their preparation and their use
DE4210253.7 1992-03-28
US3154693A 1993-03-15 1993-03-15
US28900794A 1994-08-11 1994-08-11
US08/688,354 US5814289A (en) 1992-03-28 1996-07-30 Process for the peparation of cogranulates comprising aluminosilicates and sodium silicates

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6300303B1 (en) 1997-12-19 2001-10-09 Clariant Gmbh Phyllosilicate-containing detergent and cleaner component
US6521585B1 (en) * 1995-11-06 2003-02-18 Kao Corporation Method for producing crystalline alkali metal silicate granules and granular high density detergent
CN111433013A (en) * 2017-06-29 2020-07-17 索理思科技开曼公司 Water stable granules and tablets

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0021267A1 (en) * 1979-06-18 1981-01-07 PQ Corporation Agglomerated zeolite ion exchanger
US4652391A (en) * 1984-09-22 1987-03-24 Henkel Kommanditgesellschaft Auf Aktien High powder density free-flowing detergent
EP0249163A2 (en) * 1986-06-13 1987-12-16 Henkel Kommanditgesellschaft auf Aktien Detergents containing granular, agglomerated sodium metasilicate, process for their preparation and their use
US4728443A (en) * 1984-05-05 1988-03-01 Hoechst Aktiengesellschaft Textile softening detergent composition
US4737306A (en) * 1985-07-24 1988-04-12 Kenkel Kommanditgesellschaft Auf Aktien Layered silicates of limited swelling power, a process for their production and their use in detergents and cleaning preparations
US4820439A (en) * 1984-04-11 1989-04-11 Hoechst Aktiengesellschaft Washing and cleaning agent containing surfactants, builder, and crystalline layered sodium silicate
US4834902A (en) * 1986-07-18 1989-05-30 Henkel Kommanditgesellschaft Auf Aktien Process for the production of free-flowing alkaline detergents by compacting granulation
JPH01153800A (en) * 1987-12-11 1989-06-15 Lion Corp Concentrated flexibilizing granular detergent composition
US4861510A (en) * 1987-01-24 1989-08-29 Henkel Kommanditgesellschaft Auf Aktien Porous layer silicate/sodium sulfate agglomerate
EP0405122A2 (en) * 1989-06-24 1991-01-02 Hoechst Aktiengesellschaft Builder for fabric detergent
DE3942066A1 (en) * 1989-12-20 1991-06-27 Henkel Kgaa METHOD FOR PRODUCING A GRANULAR AVIVATING DETERGENT ADDITIVE
WO1991009927A1 (en) * 1989-12-27 1991-07-11 Henkel Kommanditgesellschaft Auf Aktien Granular, brightening detergent additive and process for manufacturing it
US5108646A (en) * 1990-10-26 1992-04-28 The Procter & Gamble Company Process for agglomerating aluminosilicate or layered silicate detergent builders
US5378388A (en) * 1993-06-25 1995-01-03 The Procter & Gamble Company Granular detergent compositions containing selected builders in optimum ratios
US5393455A (en) * 1990-10-26 1995-02-28 Henkel Kommanditgesellschaft Auf Aktien Zeolite-based phosphate-free detergent builder composition

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0021267A1 (en) * 1979-06-18 1981-01-07 PQ Corporation Agglomerated zeolite ion exchanger
US4820439A (en) * 1984-04-11 1989-04-11 Hoechst Aktiengesellschaft Washing and cleaning agent containing surfactants, builder, and crystalline layered sodium silicate
US4728443A (en) * 1984-05-05 1988-03-01 Hoechst Aktiengesellschaft Textile softening detergent composition
US4652391A (en) * 1984-09-22 1987-03-24 Henkel Kommanditgesellschaft Auf Aktien High powder density free-flowing detergent
US4737306A (en) * 1985-07-24 1988-04-12 Kenkel Kommanditgesellschaft Auf Aktien Layered silicates of limited swelling power, a process for their production and their use in detergents and cleaning preparations
EP0249163A2 (en) * 1986-06-13 1987-12-16 Henkel Kommanditgesellschaft auf Aktien Detergents containing granular, agglomerated sodium metasilicate, process for their preparation and their use
US4834902A (en) * 1986-07-18 1989-05-30 Henkel Kommanditgesellschaft Auf Aktien Process for the production of free-flowing alkaline detergents by compacting granulation
US4861510A (en) * 1987-01-24 1989-08-29 Henkel Kommanditgesellschaft Auf Aktien Porous layer silicate/sodium sulfate agglomerate
JPH01153800A (en) * 1987-12-11 1989-06-15 Lion Corp Concentrated flexibilizing granular detergent composition
EP0405122A2 (en) * 1989-06-24 1991-01-02 Hoechst Aktiengesellschaft Builder for fabric detergent
DE3942066A1 (en) * 1989-12-20 1991-06-27 Henkel Kgaa METHOD FOR PRODUCING A GRANULAR AVIVATING DETERGENT ADDITIVE
WO1991009927A1 (en) * 1989-12-27 1991-07-11 Henkel Kommanditgesellschaft Auf Aktien Granular, brightening detergent additive and process for manufacturing it
US5108646A (en) * 1990-10-26 1992-04-28 The Procter & Gamble Company Process for agglomerating aluminosilicate or layered silicate detergent builders
US5393455A (en) * 1990-10-26 1995-02-28 Henkel Kommanditgesellschaft Auf Aktien Zeolite-based phosphate-free detergent builder composition
US5378388A (en) * 1993-06-25 1995-01-03 The Procter & Gamble Company Granular detergent compositions containing selected builders in optimum ratios

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6521585B1 (en) * 1995-11-06 2003-02-18 Kao Corporation Method for producing crystalline alkali metal silicate granules and granular high density detergent
US6300303B1 (en) 1997-12-19 2001-10-09 Clariant Gmbh Phyllosilicate-containing detergent and cleaner component
CN111433013A (en) * 2017-06-29 2020-07-17 索理思科技开曼公司 Water stable granules and tablets
EP3645258A4 (en) * 2017-06-29 2021-03-31 Solenis Technologies Cayman, L.P. Water stable granules and tablets

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